1. Field of the Invention
The invention relates to an optical semiconductor device. More particularly, the invention relates to an optical semiconductor device in which a semiconductor chip having an optical element is resin-sealed in a package.
2. Related Art
Reduction in size of electronic equipments has been rapidly progressed in recent years. Reduction in size has therefore been increasingly demanded for optical semiconductor devices for use in the electronic equipments. Optical semiconductor devices are formed by, for example, accommodating a semiconductor chip having an optical element formed thereon in a package having a window portion, and sealing the window portion by a transparent member such as a protective glass. Conventionally, in order to reduce the size of the optical semiconductor devices, the bonding width of the transparent member is reduced as well as the distance from the outer shape of the transparent member to the outer shape of the package is reduced so that the width of a recessed sidewall portion is reduced.
An optical semiconductor device formed by directly fixing a transparent member onto a semiconductor chip having an optical element formed thereon, accommodating the resultant semiconductor chip in a recessed package, and filling the package with a sealing resin is also known in the art (for example, Japanese Laid-Open Patent Publication No. SHO61-123288). Such a resin-sealed optical semiconductor device is capable of further reduction in size and thickness as compared to an optical semiconductor device having a window portion sealed by a transparent member.